BufferStream.php in Zircon Profile 8

Namespace

GuzzleHttp\Psr7

File

vendor/guzzlehttp/psr7/src/BufferStream.php

<?php

namespace GuzzleHttp\Psr7;

use Psr\Http\Message\StreamInterface;

/**
 * Provides a buffer stream that can be written to to fill a buffer, and read
 * from to remove bytes from the buffer.
 *
 * This stream returns a "hwm" metadata value that tells upstream consumers
 * what the configured high water mark of the stream is, or the maximum
 * preferred size of the buffer.
 */
class BufferStream implements StreamInterface {
  private $hwm;
  private $buffer = '';

  /**
   * @param int $hwm High water mark, representing the preferred maximum
   *                 buffer size. If the size of the buffer exceeds the high
   *                 water mark, then calls to write will continue to succeed
   *                 but will return false to inform writers to slow down
   *                 until the buffer has been drained by reading from it.
   */
  public function __construct($hwm = 16384) {
    $this->hwm = $hwm;
  }
  public function __toString() {
    return $this
      ->getContents();
  }
  public function getContents() {
    $buffer = $this->buffer;
    $this->buffer = '';
    return $buffer;
  }
  public function close() {
    $this->buffer = '';
  }
  public function detach() {
    $this
      ->close();
  }
  public function getSize() {
    return strlen($this->buffer);
  }
  public function isReadable() {
    return true;
  }
  public function isWritable() {
    return true;
  }
  public function isSeekable() {
    return false;
  }
  public function rewind() {
    $this
      ->seek(0);
  }
  public function seek($offset, $whence = SEEK_SET) {
    throw new \RuntimeException('Cannot seek a BufferStream');
  }
  public function eof() {
    return strlen($this->buffer) === 0;
  }
  public function tell() {
    throw new \RuntimeException('Cannot determine the position of a BufferStream');
  }

  /**
   * Reads data from the buffer.
   */
  public function read($length) {
    $currentLength = strlen($this->buffer);
    if ($length >= $currentLength) {

      // No need to slice the buffer because we don't have enough data.
      $result = $this->buffer;
      $this->buffer = '';
    }
    else {

      // Slice up the result to provide a subset of the buffer.
      $result = substr($this->buffer, 0, $length);
      $this->buffer = substr($this->buffer, $length);
    }
    return $result;
  }

  /**
   * Writes data to the buffer.
   */
  public function write($string) {
    $this->buffer .= $string;

    // TODO: What should happen here?
    if (strlen($this->buffer) >= $this->hwm) {
      return false;
    }
    return strlen($string);
  }
  public function getMetadata($key = null) {
    if ($key == 'hwm') {
      return $this->hwm;
    }
    return $key ? null : [];
  }

}

Classes

Name	Description
BufferStream	Provides a buffer stream that can be written to to fill a buffer, and read from to remove bytes from the buffer.